On 9/11, children who were residents of the World Trade Center area or students in local schools experienced a wide range of psychological traumas and of toxic exposures. To ensure their long term well- being of individuals exposed to 9/11 as children, it is imperative that we understand the longitudinal, lifetime effects that these traumatic and toxic exposures are having on their physical health and behavioral development. Yet the bulk of research has focused on those who were adults on 9/11. This research has furnished strong evidence linking 9/11 traumatic and toxic exposures (both on 9/11 and subsequently) to a wide range of subsequent adult psychiatric and physical disorders. Based on this research, much of it related to The World Trade Center Health Registry (WTCHR), we unfortunately can expect that youth who were directly exposed to 9/11 during sensitive periods in their physical and mental development will carry even greater and ongoing lifetime risks for a variety of behavioral and physical health difficulties. It is thus imperative to study these individuals over the long term, both to facilitate early intervention and amelioration for 9/11 exposed individuals, and to amortize this rare cohort to help us better understand the lifetime developmental impact of childhood trauma and toxicity for all the other children that may have been, or may yet become, so exposed. Yet, surprisingly, much less research has been done with those exposed to 9/11 as children. Our team, The Child Psychiatric Epidemiology Group (CPEG) has begun to fill in this gap with our own in depth mental health follow up evaluation of individuals in this sample in our funded Stress and Well Being (S&W) study. The S&W study followed N=1,000 individuals exposed to 9/11 as children and N=500, age and gender matched, unexposed Controls. It was focused on psychological trauma and psychiatric and behavioral outcomes, and produced concrete evidence for the ongoing developmental psychiatric and behavioral problems in this group, a decade after 9/11. We therefore now propose to conduct an expansion of the scope of this study by assessing these individuals for toxic as well as traumatic exposures and to follow their physical health (airway disorders and inflammatory processes) as well as their ongoing psychiatric (mental health, substance abuse) and behavioral (decision anomalies and high-risk behavior) outcomes. In addition we will be in a position to examine the interaction between traumatic and toxic exposures and the resulting comorbidities of physical and mental health issues. This will fill important knowledge gaps, resulting in valuable information to guide both psychiatric and general medical care for those children exposed to 9/11 and the ensuing toxicity, while simultaneously providing new information relevant for other youth exposed to other traumatic events.